Drilling or tapping machine



Apri 5, 1932,. E. LoNNELL DRIIIJLING OR TAPPING MACHINE FledY May 23. 1929v 3 Sheets-Sheet l Palmi.

April 5, 1932 'a L. CQNNELL DRILLING OR TAPPING MACHINE Filed May 23, 1929 5 Sheets-Sheet 2 mvENroR r n.. www E w C @r L M W.

f my Aprnl 5 E932. E. 1 coNNELL 852973@ DRILLING OR TAPPING MACHINE Filed may? 23, 1929y s Sheets-sheet :5

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mama Apr. s', 1932 i nnwnrr.. com, or omo, Assranon To Iroor. co., or CLEVELAND. omo,4

'rma vnr non nimm n conoaarron or omo Damme on Tarrina noma Application led Kay-23, 1929. Serial No. 885,358.l

This invention relates to motor driven machines, itsv object being to provide a simple and im roved arrangement of controlmechanism aptable for use on either drilling, tapl ing, stud setting or like 4 ev'lsed as to terminate the drilling, tapping or stud setting operation` by the torque resistance andrestore the motor to o rative condition by the usualoperation o retracting the 1I tool from the work, whereby the machine is more or less automatic in operation, but nevertheless is controlled by the operator with his usual manipulations of such machines.

Further objects of the inventionare in part obvious and in part will appear more in detail hereinafter.

In the drawings, Fig. 1 represents a front elevation of a portion of a drilling machine embodying the invention; Fig. 2 is a detail elevation illustrating the switch mechanism, the cover of the switch casing bein omitted for the clearness` of illustration; 1g. 3 is a sectionalplan view through the cover of the switch, the section being taken on approximately the line 3 3, Fig. 1; Fig. 4 is a .detail section on the line 44, Fig. 2; Fig. 5 is a sectionalelevatinof a tapping or stud setting machine embodying the invention; Fig. l6 is aA sectional'elevation through the controlling portion of ythe operating handle; and Fig. 7 is a wiring diagram of the control system.

The drilling'machine shown in Fig. 1 comprises an arm or support 1 mounted to swing about and also adjustable vertically upon a post or column, not shown. lThis `radial arm carries a' head lor frame 2 including a post 3 provided with a head 4l carrying a bearing sleeve 5 in which is vertically slidable a rod or shaft 6 attached to a sub-frame 7 in which l is mounted, preferably detachably, a portable tool, such as a portable electric drill indicated generally at 8 and including an electric motor,

ing, and a tool spindle 9. The sub-'frame 7 10 guided y and travelling along the post 3. A compression spring 11 adjustable bythe 12 serves to normally elevate the submachines, and so Iergization of I said lts casing, any necessary speed reducing gearframe 7 and the tool carried therebyfto the upper most position. The tool is brought into engagement with the. work by the operator, who depresses a handle or lever 13 pivoted at 14 upon the sub-frame and having a short arm connected by a link 15 to the head 4.

The electricalcontrol system for this tool is shown in Fig. 7, where the three wire A. C. circuit leads 16a, 16?` and 160' are connected to the main, switch, indicated generally at 17, and including contacts 18 in all of said leads actuated by a relay coil 19 adapted upon encoil to close the main switch and complete the circuits to the motor M. i The main switch also carriesl an extra set of controlling contacts,'marked 20, 'which are in a circuit 21 from one of the leads, such as 16a, with a normallyclosed overload switch 22, a normally closed gauge stop switch 23, (if use of such a stop is desirable) a normally c losed'emergency stop switch 24, and coil 19 to another lead 1Gb. The control 'circuits also include a starting circuit 25 in circuit with the normally open start switch 26.

In the arrangement shown in Fig. 1 a gauge stop is not used but it may be employed, as will appear.

In the usek of thisapparatus the moto'r isA started by closing vthe starting switch 26, which energizes coil .19 through the normally closed stop button 24 and closes the motor circuits at the main switch. Control contacts 20 are also closed, thereby establishing a maintaining circuit by way of contacts 20, switches 22, 23 and 24 through the coil 19 and permitting the start switch to be released and move to open, position. The motor will continue to run. The operator pulls down the lever 13 and then applies the tool to the work.

The tool may be a drill, a tap,`a stud'or nut.

setter, or the like. Assuming that a bolt is to be screwed home in an engine block, when 'the bolt reaches its home position considerable torque resistance is immediately encountered, causing arush or rise of current'flow through an overload coil 27 in one'of the motor leads, thereby actuating a movable core to open the switch 22 and break the circuit to the coil 19, thereby opening the motor circuits and con .tacts 20. The overload switch 22 is normally lil@ . self-closing form,

Yopen when 1 ducting roller 31 carried by an arm or lever.

closed,l or in lother words, islof any suitable in the sense that -it is only the overload coil 27 is energized, and at any the form shown in Fig. 2. It includes a cas- 28 mounted on one side of the head 4 and in which is located an arcuate insulating block 29 carrying Itwo loppositely dis osed similar conducting segments 30, 30a. ooperating with said segments is a yielding con- 32 pivoted at 33 and connected by a link 34 to the movin of the su -frame swings the lever 32. On the cover 28a of the switch casing is the normally closedyielding stop button switch 24, shown ih Fig. 3. Circuit wires from this switch lead one to the conducting segment 30 and the other to the main relay coil 19.V Segment 31 is also connected by a wire35, 36 to the overload switch' 22,. Segment 30a is lon the opposite side of block 29 and insulated from segment 30. As the roller 31 travels along its arcuate path it simultaneously engages the segments 30 and 30a and conductively bridges them, thereby/ l completing the startlng circuit.

Fig. '2 shows the switch parts-in `the position corresponding to Fig. 1, with the tool in its uppermost position. The starting switch 26 is therefore energized by the travel of the -tool toward its upper position, or will be energized upon the first depression of the tool by the handle 13, which causes roller 31 to contact simultaneously with the segments 30 and 30a, and thereby complete the circuit 21, 25, 26, 24, 19, Fig. 7, and energizes coil 19, thus closing contacts 2O and maintaining said contacts and themotor circuit closed -evenl when the tool is further depressed and roller 31 reaches the insulated part 29 of the seg,

ment. As before stated, the tool is engaged with the work and performs its duty until the over-load coil 27 opens switch 22, whereupon the motor circuit is opened, the motor stops, switch 22 promptly closes, and the operator disengages the toolpfrom the work and moves or permitsv it to move to its uppermost position, thereupon instantaneously completing the starting circuit b closing of the starting switch, as before. e tool is therefore operating and ready for another cycle of duty as before, but the operator need give no-attention -to the control mechanism except to press the emergency o'r stop button 24 when he wants to stop the tool at other times than by the operation aforesaid. A

Figs. 5 and `6 show another embodiment of the invention` particularly adapted for screwingor threading operations, such as tapping,

including a tool head'40 on which is mounted a driving motor 41 connected by the geartime when said coil is deenerglzed' the switch 22 promptly moves of itself-'to-4 sub-frame 7 ,.so that motionl by rollers in ing generally represented at 42 to 'drive a shaft 43 provided with twopinions 44, 45, the former engagin a pinion 46 splined on a longitudinally slida le sleeve member 47, and thelatter engaging an intermediate pinion 48 reversely driving a pinion 49 splinedon a longitudinally slidable` sleeve 50, sleeves -47 and 50 being interconnected by the ball bearing 51 but rotating `inopposite directions. The upper sleeve 47 carries a forwardly driving clutch member 52 and the 'lower sleeve a reversely driving clutch member 53, the two clutch members cooperating with a clutch member 54 upon the tool `spindle 55, which 'slides' and rotates in both sleeves, its move- ,ment beinglimited by collars 55a, 556 at-its upper and lower ends. lThe lower sleeve `50 is provided with a grooved collar 56 engaged lever or arm 57 connected by a linky 58 to a stationary point on the main frame. The lever also carries a gauge stop 59 adjustable as to length and having a gauge portion 60 designed to engagethe work when a desired depth or home yposition is-reached, and also including a shank 61 travelling in a guide 62 and normally held downwardly by .a

spring 63. At. the upper end of said rod 59 is the switch 23, including a bridge Contact cooperating with stationary .contacts and forming the normally closed but fopenable switch conventionally indicated in Fig. 7.

The starting switch in this arrangement is of the form shown in Fig. 6. The lever 57 is of elbow form having a handle portion 65 pivoted at 66 and carrying two fingers 67, 68 which limit its swinging movement on the lever. One of said fingers carries a member 69 adapted to engage and-depress a push button 70 for actuating a yieldable normally open switch 26, the details of which are immaterial except that the pressure of the spring 27a which normally opens the switch may be fairly strong for reasons which will appear.

In this arrangement the tool spindle 55 and the coupled sleeves 47, 50 move downwardly by gravity. The control system is of the same form shown in Fig. 7, the main switch and overload coil being conveniently mounted on any suitable support, such as a part of the frame 40. v

Assuming the machine at rest, the lever 57 is raised by raising the handle 65, which disengages the upper clutches-and enga es the lower reverse clutches,'furtherfu war movement of the handle 65 against t e weight of the sleeves and tool spindle being suiicient to overcome the pressure of springl 27 a and close the yielding switch 26, which starts the'motor and establishes the maintaining circuit through'contacts 20 and coil 19 before'referred to. The handle is then lowered and the 'sleeves and tool spindle being suiiicient to the tool is applied to the work, its advance being stopped while thevsleeves 47, 50 move the motor stops.

assenso downwardly until the toolrotates forwardly,

whereupon the tool is screwed into the work until gauge 60 opens switch 23 or until the toilue rise causes current rise in the coil 27 su cient to open the switch 22 whereupon the motor circuits are brolxen and from the forward clutches and the operator raises the handles 65, and sleeves 47, 50, thereby rst opening the forward clutch and closing the reverse clutch, Whereu on further 'elevating movement of the hand e 65 closes the starting switch and re-enerriven in the reverse direction and t e tool is `retracted from thework.A This leaves the machine with the motor running. ready for another operation, even through the operator has performed no more than his customary manipulations.

What I claim is:

1. Apparatus ofthe class described, comprising a tool and reciprocating motion,'an electric motor and circuit for rotating'said spindle, a control crcuit, a'relay therein for controlling both the motor circuit and the control cir` cuit, normally closed switch means in the control circuit for controlling the motorcircuit, means sensitive to the current su plied to the motor .through the motor circuitiortuating said switch means to open the control circuit, thereby causing said relay to open the motor circuit, an operator operated decontrol circuit for controlling the motor circuit, means sensitive to the current supplied to the motor through the motor circuit for actuating said switch means to open the control circuit, thereby causing said relay to' open the motor circuit, an operator-operated device for producing reciprocating lmotion of said tool spindle, and switch means actuated by reciprocating motion of said tool spindle for affecting said relay toA complete the motor circuit. .e 4

In .testimony whereof I hereby aix my signature.

EDWIN A L. CONNELL.

This takes-the load of.

izes the motor so that the tool s indle isr spindle mounted for rotating i y Mutuo. f

EDWIN l; coNNELL. AIt is kerel-1y ce-rtified that errorcpp I 4in the printed spccif-cationof the numbered patent requiring correct Van followng, PagevZ, line '128,l strike und Letters Patent should be read with thss'correcti'cn therein bcing'sn'fficicnt to"; and thatV the that the sam;

my confcm to the cordwcfn'thefmcfin the Patent ffic.

signeama nigga-fusi 17th-hy of May, A. D,193 2 I (ScaliA I' M..., J. Heere, Acting Cmlnissoncr of Patents,

. cfmen'mil s, 1932, :o 

